/* xmalloc.c -- malloc with out of memory checking
   Copyright (C) 1990-1999, 2000, 2002 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#if HAVE_CONFIG_H
# include <config.h>
#endif

#include <sys/types.h>
#include <stdlib.h>
#include <memory.h>
#include <string.h>

#include "gettext.h"
#include "error.h"
#include "xalloc.h"

#define NULL 0
#ifndef EXIT_FAILURE
# define EXIT_FAILURE 1
#endif

/* Exit value when the requested amount of memory is not available.
   The caller may set it to some other value.  */
int xalloc_exit_failure = EXIT_FAILURE;

/* If non NULL, call this function when memory is exhausted. */
void (*xalloc_fail_func) (void) = 0;

/* If XALLOC_FAIL_FUNC is NULL, or does return, display this message
   before exiting when memory is exhausted.  Goes through gettext. */
const char xalloc_msg_memory_exhausted[] = "memory exhausted";

void xalloc_die (void)
{
  if (xalloc_fail_func)
    (*xalloc_fail_func) ();
  error (xalloc_exit_failure, 0, "%s", xalloc_msg_memory_exhausted);
  /* The `noreturn' cannot be given to error, since it may return if
     its first argument is 0.  To help compilers understand the
     xalloc_die does terminate, call exit. */
#if defined(OS_LINUX)
  exit (EXIT_FAILURE);
#elif defined(OS_WIN)
  throw (NULL);
#else
  NOT_IMPLEMENTED();
#endif
}

/* Allocate N bytes of memory dynamically, with error checking.  */

void* xmalloc (size_t n)
{
  void *p;

  p = malloc (n);
  if (p == 0)
    xalloc_die ();
  return p;
}

/* Change the size of an allocated block of memory P to N bytes,
   with error checking.  */

void* xrealloc (void *p, size_t n)
{
  p = realloc (p, n);
  if (p == 0)
    xalloc_die ();
  return p;
}

/* Allocate memory for N elements of S bytes, with error checking.  */

void* xcalloc (size_t n, size_t s)
{
  void *p;

  p = calloc (n, s);
  if (p == 0)
    xalloc_die ();
  return p;
}

char *xstrdup (const char *str)
{
  if (str == NULL)
    return NULL;
  size_t len = strlen(str) + 1; // We +1 because strlen doesn't return the len with the last caracter (\0).
  char * ret = (char*)malloc(len);
  memcpy(ret, str, len);
}